Trying to install a new GPU and it's not being used or showing up on Task Manager.

I've inserted a new RX550 into my Optiplex 5060 and installed the drivers for it, but it still doesn't seem to be working and Task Manager is only displaying the integrated GPU. How can I get it to switch over?

Windows 11, Intel Core i7-8700 CPU, Intel UHD Graphics 630, 16gb RAM. I believe its power supply is 260W